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Finding the Fourth Proportional to 12.72, 17.56 and 6.90

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Solution

The fourth proportional to 12.72, 17.56 and 6.90 is: 9.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    12.72 : 17.56 = 6.90 : x
  2. Step 2: Convert to fraction form
    12.72/17.56 = 6.90/x
  3. Step 3: Cross multiply
    12.72x = 17.56 × 6.90
  4. Step 4: Simplify right side
    12.72x = 121.08
  5. Step 5: Solve for x
    x = 121.08/12.72
  6. Step 6: Final answer
    x = 9.52

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.